This project examines the effects of biomedical ultrasound, alone and in combination with hyperthermia, on mammalian cells in monolayer culture. Specific endpoints to be studied include: (1) Cell lethality as a function of intensity and exposure duration for continuous wave exposure, (2) cell lethality as a function of pulse length for pulsed exposure, and (3) the possible induction of chromosomal anomalies. The results will be used in evaluating the potential risks from diagnostic and therapeutic applications of ultrasound, and the possible benefits from the use of ultrasound as a cancer therapeutic agent.